This invention relates to manually-operated reciprocating fluid pumps such as pump-type trigger sprayers.
A trigger sprayer typically includes a dispenser body, a closure cap connected to the dispenser body for securing the trigger sprayer to the mouth of a container (or bottle), a dip tube depending from the dispenser body and configured for extending into the bottle, and a gasket for preventing leakage between the closure cap and the mouth of the container when the closure cap closes the mouth of the container.
The dispenser body has a manually operated pump which draws liquid up the dip tube from the bottle and dispenses it through a nozzle via a liquid flow path in the dispenser body. A priming check valve within the liquid flow path and upstream of the pump permits fluid flow from the container to the pump, but checks fluid flow from the pump back to the container. Another check valve within the liquid flow path and downstream of the pump permits fluid flow from the pump to the nozzle, but checks fluid flow from the nozzle to the pump.
A concern associated with such trigger sprayers is that a gasket occasionally falls out of its associated closure cap. A gasket might be pried out of its closure cap via a dip tube of another trigger sprayer while the trigger sprayers are being assembled and/or transported. If a gasket falls out of its associated trigger sprayer during assembly, the gasket could cause a shut-down of the assembly line until the defective trigger sprayer is located. Also, if a trigger sprayer is missing its gasket when connected to a bottle, then the liquid contents of the bottle may inadvertently leak therefrom.
Another concern associated with such a trigger sprayer is the cost of manufacture. A typical trigger sprayer is of relatively low cost. However, trigger sprayers with more pieces generally cost slightly more to produce than trigger sprayers with fewer pieces. Millions of trigger sprayers are sold each year for use in dispensing a wide variety of products. Because of the large volumes sold, a savings of even one cent per trigger sprayer is significant.